Remove manual docker daemon request unpiping

Change-type: patch
See: balena-io-modules/resin-docker-build#31

lib/build/builder.ts

@@ -24,7 +24,6 @@ import * as fs from 'mz/fs';
 import * as path from 'path';
 import { Duplex } from 'stream';
 import * as tar from 'tar-stream';
-import type * as http from 'http';
 
 // Import hook definitions
 import * as Plugin from './plugin';
@@ -84,7 +83,6 @@ export default class Builder {
 		const failBuild = _.once((err: Error) => {
 			streamError = err;
 			dup.destroy(err);
-			cleanupDaemonStream?.();
 			return this.callHook(
 				hooks,
 				'buildFailure',
@@ -98,8 +96,6 @@ export default class Builder {
 		inputStream.on('error', failBuild);
 		dup.on('error', failBuild);
 
-		let cleanupDaemonStream: (() => void) | undefined;
-
 		const buildPromise = (async () => {
 			const daemonStream = await this.docker.buildImage(inputStream, buildOpts);
 
@@ -109,27 +105,10 @@ export default class Builder {
 					layers,
 					fromTags,
 					(err) => {
-						cleanupDaemonStream = () => {
-							if (
-								'req' in daemonStream! &&
-								daemonStream.req != null &&
-								typeof daemonStream.req === 'object' &&
-								'destroy' in daemonStream.req &&
-								typeof daemonStream.req.destroy === 'function'
-							) {
-								const req = daemonStream.req as http.ClientRequest;
-								if (!req.destroyed) {
-									req.destroy();
-								}
-							}
-							daemonStream.unpipe();
-							cleanupDaemonStream = undefined;
-						};
 						reject(err);
 					},
 				);
 				outputStream.on('error', (error: Error) => {
-					daemonStream.unpipe();
 					reject(error);
 				});
 				outputStream.on('end', () =>
@@ -144,7 +123,7 @@ export default class Builder {
 
 		// It is helpful for the following promises to run in parallel because
 		// buildPromise may reject sooner than the buildStream hook completes
-		// (in which case the stream is unpipe'd and destroy'ed), and yet the
+		// (in which case the stream is destroy'ed), and yet the
 		// buildStream hook must be called in order for buildPromise to ever
 		// resolve (as the hook call consumes the `dup` stream).
 		Promise.all([